/*
* Copyright (c) 2012 Kyle Hayward
* 
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* 
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/

//Draw a fullscreen quad

cbuffer cbPerFrame	: register( b0 )
{
    matrix	View;
	matrix	Proj;
	matrix	ViewProj;
}

struct VS_Output
{
    float4 Pos : SV_POSITION;
    float2 Tex : TEXCOORD0;
};

Texture2D		screenTex	: register( t0 );
SamplerState	screenSamp	: register( s0 );

VS_Output VSMain( uint id : SV_VertexID )
{
    VS_Output Output;

    Output.Tex = float2((id << 1) & 2, id & 2);
    Output.Pos = float4(Output.Tex * float2(2,-2) + float2(-1,1), 0, 1);
    
    return Output;
}

float4 PSMain( VS_Output Input ) : SV_TARGET
{
	float3 color = screenTex.Sample( screenSamp, Input.Tex ).rgb;

	//gamma correct
	color = pow( abs( color ), 1.0f / 2.2f );

	return float4( color, 1.0f );
}
